1. Field of the Invention
The present invention relates to a reel around which is wound recording tape such as magnetic tape used for saving data of computers and the like and to a manufacturing method thereof.
2. Description of the Related Art
Conventionally, recording tape cartridges have been known where recording tape such as magnetic tape used as a data recording and playback medium (data backup) for computers and the like is wound onto a reel made of resin and the reel is singly housed inside a case. In the reel of the recording tape cartridge, sometimes a hub around which the recording tape is wound and an upper flange and a lower flange that hold the width direction end portions of the recording tape are formed separately (e.g., see JP-A No. 2002-133818 and JP-A No. 2005-108409).
In a reel of such a three-piece (part) structure, the upper flange is welded to the upper end portion of the hub, and the lower flange is welded to the lower end portion of the hub. Consequently, when the hub becomes deformed by the winding constriction of the recording tape, there is the potential for the upper flange and the lower flange welded to the hub to become deformed by the affects of that deformation. Further, when the upper flange and the lower flange are respectively welded to the upper end portion and the lower end potion of the hub, there is also the problem that the welding strength is not sufficiently ensured, such as there being the potential for the upper flange and the lower flange to separate from the hub during deformation.